function combine_Music(){
var data = new FormData();
data.append( "bag", sessionStorage.getItem('bag') );
fetch("/combined/",
{
    method: "POST",
    body: data
})
.then(function(response){ 
console.log(response.json())
  return response.json();
 })
.then(function(data){ alert( JSON.stringify( data ) ) })
}



fetch("/combined/",
{
    method: "POST",
    body: data
})
.then(function(response){ 
console.log(response);
  return response;
 })